im blowing black smoke

my stepdad notived that my car started belching black smoke from the exhaust. it only happens in upper rpms when im in the throttle. Black means too much fuel right? My dad said it may be the o2 sensor going bad. What are some other things to check before i replace the O2? Could i possibly run some seafoam through it?

Edit:I just checked my plugs and im running lean (white). Possibly clogged injectors? Could it be burning oil perhaps? I know oil makes blue smoke but still its a possibilty

it could be oil, although like you said, blue smoke usually indicates burning oil. Do a compression check you might have a bad headgasket if thats the case. Pull the injectors off and clean them and check your fuel filter.

You don't have an AFC or any or thing that will mess with fuel delivery do you?

fix the 02 sensor....black is rich, white is water, blue is oil.....fun is when its all of the above...

Black smoke is fuel as said before. Running seafoam won't really do anything much to make it better. I'd go with your dad's advice and check the o2 sensor. I'm not sure for honda's but with dsm's when it is like partially dead it won't trigger a CEL but you will notice decreased fuel economy and you will run more rich. When it dies you'll know my mileage in my talon dropped to around 7mpg from 20mpg when mine died. Their not expensive and it's easy to install so I'd go for it.
-Andrew

My motor and ecu are stock except the exhaust...and thats not really even part of the engine. It still sips fuel. I havent noticed a decrease in performance either although it didnt have hardly any hp to lose in the first place. Any clues as to why the plugs say im lean when the smoke is black?

yah, get that 02 sensor replaced ASAP. Usually you'll get a CEL, but when something like that goes out the ecu usually goes into limp mode, making your car run rich.

compression test says? difference in fuel consumption? you checked the spark plugs at wot with new plugs?

i just suggested it because he said he thinks he might be burning oil even though he's getting black smoke. Just trying to cover all bases.